Out-of-balance weight assemblies

ABSTRACT

An out-of-balance weight assembly as used for example on vibratory sieves, shakers tables, ball mills or the like, and comprising a weight having an eccentric bush adjustably mounted in a bore in the weight. Means to restrain relative movement between the weight and the bush, and the bush and a driving shaft are provided. The out-of-balance balance component, and/or the angle thereof relative to the shaft when the shaft is rotated may be varied by rotational adjustment of the weight and/or the bush about the shaft.

Unite States Patent 1 1 3,771,374 Choules Nov. 13, 1973 [54]OUT-OF-BALANCE WEIGHT ASSEMBLIES 3,491,881 1/1970 Winquist 74/61 X3,640,50 2 R [75 Inventor: Marcel Henry Choules, Surrey, 8 2/197 elblg74/87 X England Primary ExaminerAllan D. Herrmann [73] Assignee: RussellFinex Limited, London, Att j h Mawhinney England [21] Appl' 279885 Anout-of-balance weight assembly as used for example on vibratory sieves,shakers tables, ball mills or the like, and comprising a weight havingan eccentric bush adjustably mounted in a bore in the weight. Means torestrain relative movement between the weight and the bush, and the bushand a driving shaft are provided. The out-of-balance balance component,and/or the angle thereof relative to the shaft when the shaft is rotatedmay be varied by rotational adjustment of the weight and/or the bushabout the shaft.

9 Claims, 3 Drawing Figures [30] Foreign Application Priority Data Aug.16, 197] Great Britain ..38375/7l [52] U.S. Cl. 74/87, 259/DlG. 42 [51]Int. Cl. Fl6h 33/10 [58] Field of Search 74/61, 87; 259/DIG. 42;209/3665 [56] References Cited UNITED STATES PATENTS 2,774,244 l2/1956Bergstrom et al. 74/6l 3,097,537 7/1963 Peterson 74/ 6 l OUT-OF-BALANCEWEIGHT ASSEMBLIES BACKGROUND OF THE INVENTION The invention relates toout-of-balance weight assemblies for use on vibratory apparatus such as,for example, sieves, strainers, balls mills, tables and the like. It isfrequently desirable in such vibratory apparatus to vary the magnitudeof the out-of-balance component generated by the assembly, and it iscommon to attach or remove subsidiary weights to a main weight in orderto vary the out-of-balance component. In addition, and in particularwhen two out-of-balance weights are connected together for jointrotation, it is frequently desirable to alter the angle between theout-of-balance components generated by the two weights.

SUMMARY OF THE INVENTION It is an object of the invention to provide anout-ofbalance weight assembly in which the out-of-balance component andthe angle thereof with respect to a driving shaft may be readily andeasily adjusted. In accordance with this object, the invention providesan outof-balance weight assembly comprising a weight, a bore extendingthrough the weight, a bush fitting within said bore, means for adjustingthe bush about the axis of said bore, the bore of the bush beingeccentrically disposed relative to the outer surface of the bush andbeing capable of receiving a driving shaft for the weight, and means torestrain the bush against rotation with respect to the weight and withrespect to the shaft, whereby the out-of-balance component or the anglethereof with respect to the shaft generated by rotation of the weightabout the axis of the bore of the bush may be varied by adjusting thebush in the bore of the weight.

The weight may be provided with a slot extending between the bore of theweight and the outer periphery of the weight for the length of the bore,the restraining means being arranged to close the slot to clamp theweight to the bush.

The wall of the eccentric bush may be discontinuous so that when thebush is mounted on a shaft and the weight is clamped to the bush, thebush is also clamped to the shaft.

In any of the above arrangements the means for adjusting of the bushwith respect to the weight may comprise a lever attached to the bush andextending radially outwardly therefrom.

The adjusting meansmay include means to indicate the relative angularposition of the bush with respect to the weight.

Means may be provided for indicating the relative angular position ofthe out-of-balance weight assembly with respect to a datum provided on ashaft on which the assembly is mounted.

BRIEF DESCRIPTION OF THE DRAWINGS The following is a description of onepreferred embodiment of the invention, and given by way of example.Reference is made to the accompanying drawings in which:

FIG. 1 is a plan view of an adjustable out-of-balance weight assembly;

FIG. 2 is a view on arrow A on FIG. 1; and

FIG. 3 is a view on arrow B on FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT The out-of-balance weightassembly is intended for clamping to a driving shaft 10, which, in theembodiment shown in the drawings, is a stub driving shaft which projectsfrom an electric motor 11, or from a vibrator housing.

The out-of-balance weight 12 of the assembly is generally semi-circular,and has a pair ofjaws 13, 14, projecting from the edge 15 of the mainbody thereof. The inner surfaces of the jaws together with a part of thebase wall define a cylindrical bore 16 formed in the weight. The jawsterminate in flanges 17 and 18 lying substantially parallel to oneanother and closely spaced apart, there being a hole 19 extendingthrough the two flanges substantially perpendicular to their planes. Thehole 19 in the flange 18 is threaded to receive a bolt 20 which fitswith clearance through the hole 19 in the other flange 17. Tighteningthe bolt closes the gap between the two flanges 17 and 18.

Located within the bore 16 is a split bush 21, the outer surface ofwhich is cylindrical and fits closely within the bore 16, and the innersurface of which is also cylindrical and fits closely around the shaftIOQThe axis of the inner surface is eccentric with the outer surface.The wall of the bush 21 is discontinuous at a location 22 part-waybetween the parts of the bush having greatest and least radial wallthickness. The discontinuity may be at any other part of the bush, butis preferably at the location shown.

A lever 23 is welded to the part of the bush having the greatest wallthickness, and extends radially outwardly therefrom, lying adjacent theradial surface of the weight, the end 24 of the lever being turneddownwardly to lie perpendicular to the general plane of the lever. Atriangular pointer 25 is welded to the lever 23 and upstands therefromto lie adjacent the cylindrical periphery of the weight. The cylindricalperiphery of the weight is calibrated as shown at 26, against which thepointer 25 indicates.

The shaft 10 is provided with. a keyway 27, there being a furtherpointer 28 lying over the upper radial surface of the weight 12 andhaving an eye 29 encircling the shaft. The eye 29 is provided with a lug30 which engages the keyway 27, and the radially outer end 31 ofthefurther pointer 28 is turned over to lie adjacent the cylindricalperiphery of the weight 12. Further calibrations 32 are provided on thecylindrical periphery of the weight, against which the further pointerindicates the relative angular position of the weight with respect tothe keyway 27 on the shaft 10.

The shaft 10 is provided with a shoulder 33 on which one end of the bush21 abuts, and the assembly is restrained on the shaft bymeans of a flatwasher 33 abutting the other end of the bush and the lower radial faceof the weight, the washer 33 being held in place by a bolt 34 threadedinto an axially extending threaded bore provided in the shaft 10.

In use, the weight 12 is clamped to the bush 21 by tightening the bolt20, which thus deforms the shape of the bore 16. Clamping the weight onto the split bush 21 also clamps the bush 21 on to the shaft 10, wherebya driving connection is achieved between the shaft and the weight 12.The amplitude of the out-of-balance force produced when the weightassembly is rotated may be varied by loosening the bolt 20 and rotatingthe split bush 21 relative to the weight 12, by means of the lever 23,and then retightening the bolt 20. The amplitude is indicatedempirically on the calibrations 26.

When the bolt is loosened, the angular position of the weight assembly,and hence the direction of the out-ofbalance force when the assembly isrotated, with respect to a datum on the shaft may be varied, and theangular position relative to this datum is indicated on the calibrations32 by the further pointer. This feature is of particular applicationwhen the driving shaft carries a second out-of-balance weight assembly(which need not be adjustable. The resultant force of the two (or more,if provided) out-of-balance weights may thus be varied by changing theirrelative angular positions. For example, the motor shaft projecting fromthe housing 11 may also project from the further end (not shown) of thehousing 11', and the second out-ofbalance weight is then attached to theother end of the shaft.

Such out-of-balance weight assemblies have particular, but notexclusive, applications to various forms of vibrating apparatus, forexample, sieves, strainers, vibratory mills, and the like, where it maybe desired to vary the amplitude or force of vibrations and also tochange the angular relationship of the force to a datum or a secondout-of-balance weight.

I claim:

1. An out-of-balance weight assembly comprising a weight, a boreextending through the weight, a bush fitting within said bore, means foradjusting the bush about the axis of said bore, the bore of the bushbeing eccentrically disposed relative to the outer surface of the bushand being capable of receiving a driving shaft for the weight, and meansto restrain the bush against rotation with respect to the weight andwith respect to the shaft, whereby the out-of-balance component or theangle thereof with respect to the shaft generated by rotation of weightabout the axis of the bore of the bush may be varied by adjusting thebush in the bore of the 4 weight.

2. An out-of-balance weight assembly according to claim 1, in which theweight is provided with a slot extending between the bore of the weightand the outer periphery of the weight for the length of the bore, therestraining means being arranged to close the slot to clamp the weightto the bush.

3. An out-of-balance weight assembly according to claim 2, in which thewall of the eccentric bush is discontinuous so that when the bush ismounted on a shaft and the weight is clamped to the bush, the bush isalso clamped to the shaft.

4. An out-of-balance weight assembly according to claim 3, in which themeans for adjusting the bush with respect to the weight comprises alever attached to the bush and extending radially outwardly therefrom.

5. An out-of-balance weight assembly according to claim 4, in which theadjusting means includes means to indicate the relative angular positionof the bush with respect to the weight.

6. An out-of-balance weight assembly according to claim 5, in whichmeans are provided for indicating the relative angular position of theout-of-balance weight assembly with respect to a datum provided on ashaft on which the assembly is mounted.

7. An out-of-balance weight assembly according to claim 1, in which themeans for adjusting the bush with respect to the weight comprises alever attached to the bush and extending radially outwardly therefrom.

8. An out-of-balance weight assembly according to claim 1, in which theadjusting means includes means to indicate the relative angular positionof the bush with respect to the weight.

9 An out-ofbalance weight assembly according to claim 1, in which meansare provided for indicating the relative angular position of theout-of-balance weight assembly with respect to a datum provided on ashaft on which the assembly is mounted.

1. An out-of-balance weight assembly comprising a weight, a boreextending through the weight, a bush fitting within said bore, means foradjusting the bush about the axis of said bore, the bore of the bushbeing eccentrically disposed relative to the outer surface of the bushand being capable of receiving a driving shaft for the weight, and meansto restrain the bush against rotation with respect to the weight andwith respect to the shaft, whereby the out-of-balance component or theangle thereof with respect to the shaft generated by rotation of weightabout the axis of the bore of the bush may be varied by adjusting thebush in the bore of the weight.
 2. An out-of-balance weight assemblyaccording to claim 1, in which the weight is provided with a slotextending between the bore of the weight and the outer periphery of theweight for the length of the bore, the restraining means being arrangedto close the slot to clamp the weight to the bush.
 3. An out-of-balanceweight assembly according to claim 2, in which the wall of the eccentricbush is discontinuous so that when the bush is mounted on a shaft andthe weight is clamped to the bush, the bush is also clamped to theshaft.
 4. An out-of-balance weight assembly according to claim 3, inwhich the means for adjusting the bush with respect to the weightcomprises a lever attached to the bush and extending radially outwardlytherefrom.
 5. An out-of-balance weight assembly according to claim 4, inwhich the adjusting means includes means to indicate the relativeangular position of the bush with respect to the weight.
 6. Anout-of-balance weight assembly according to claim 5, in which means areprovided for indicating the relative angular position of theout-of-balance weight assembly with respect to a datum provided on ashaft on which the assembly is mounted.
 7. An out-of-balance weightassembly according to claim 1, in which the means for adjusting the bushwith respect to the weight comprises a lever attached to the bush andextending radially outwardly therefrom.
 8. An out-of-balance weightassembly according to claim 1, in which the adjusting means includesmeans to indicate the relative angular position of the bush with respectto the weight. 9 An out-of-balance weight assembly according to claim 1,in which means are provided for indicating the relative angular positionof the out-of-balance weight assembly with respect to a datum providedon a shaft on which the assembly is mounted.